Method and apparatus for feeding molten glass



4 Shee'tsv-Sheet- :Il

Dec.- 27, 1938. F. L.. o. wADswoRTH MTHOD AND APPARATUS FOR FEEDING MOLTEN GLASS' Filed March 21, 1954 mven'foa /r /l/f ,EL m.. I. ,n

Dec. 27, 1.938. 1 F. l.. o. wAnswoRTH 2,141,425

METHOD AND APPARATUS FOR FEDING MOLTEN GLASS 'Dea 27, v1938.` F. L. o. wADswoRTH METHOD AND APPARATUS FOR FEEDING MOI-ITEN GLASS 4 Sheets-Sheet yZ5 Filed March 2l, 1934 Dec. 1938. F. L.. t). wDswoRTi-l 'METHOD AND APPARATUS FOR FEEDING MOLTEN GLASS Filed Maoh 21, 1954 4 sheets-sheet 4 326 aas Patented Dec. 27, 1938 UNITED STATES PATENT- OFFICE to Bali Brothers poration of Indiana Company, Muncie, Ind., a cor- Application March 21, 1934, Serial No. 716,627

18 Claims.

This invention relates to the art of feedingmolten glass-and more particularly to an improved method and apparatus for feeding molten glass in a continuously owing streamand of producing a regular recurrent series of enlarged stream sections having a denite shape and contour which are adapted to be cut off in succession from the stream and delivered in rapid suclivery of the stream of molten glass under a gravity pressure or head which is greatly in excess of l0 that obtained in the usual forehearth and ow cession to the forming machine.

The principal object of my invention is toprof vide a forced ilow feeder of the pneumatic impulse type which may be effectively operated at a high speed without the use of any vacuum or suction action and which will, therefore, avoid such loss oi' time, and the resultant decreased rate of discharge, as results from the retarding action of a vacuum or partial vacuumfwhen the same is employed to control or to partially control delivery from the feeder. l

Another object of this invention is the provision of-'a single action or uni-directional impulse feed- .er in which the material above and in communication with the feed orifice is always subjected to a positive extrusion pressure or expulsion force. and in which such pressure or force is periodically varied as to intensity, thus producing a continuous but pulsating discharge of the molten substance, or a discharge at alternately accelerated and decelerated velocities of flow. and such as will produce a regularly recurrent series of enlarged stream sections of predetermined volume and shape that may be cut oil in succession from the continuously flowing stream and delivered to the molds of a forming machine as a rapid succession of separate charges.

A further object is to produce a feeder for molten glass which will not only increase the number of formed mold charges delivereddrom a single orifice per unit of time but will also reduce the time each suchmold charge is ,exposed to the cooling eiiect oi .the surrounding atmosphere during the period of its formation and delivery to a forming-machine.

still further object is to provide means ior producing a continuous and stream-like discharge diliiolten glass by the combined complementary action of gravity and a regularly varied and automaiticaily controlled super-atmospheric pressure which coact to produce a series of stream sections of predetermined volume and contour; and

for successivelyvseverlng these formed sections' from theoncoming stream of glass without retarding or interferingwith 'its free discharge flow in response to the combined gravity-pressure ac tion.. L

(Cl. dii-55) Still another object is to provide a shear or severing mechanism which will effect a proper cutting off of the preshaped stream sections at the desired intervalswith the minimum disturbance or distortion of the surface contour of the owing 5 'material and with the minimium chilling of the portions thereof engaged by the severing elements'.

A still further object is the formation and deboot construction. The attainment of this object is effected by providing a sub-forehearth member which extends a substantial distance below the floor of themain forehearth and which 15 is maintained at a predetermined constant temperature by individually controlled heating means, whereby the physical characteristics of the glass 'in the immediate proximityof the ow orice at the bottoni of this -sub-forehearth may be easily regulated independently of the conditions existing in the parentbody of molten material.

'A still further correlativa feature of my improvement is to periodically supplement the increased gravity action last referred to by a rela.- tively high air pressure on the material in the sub-forehearth and thereby obtain a substantially accelerated rate of discharge from the ow orlce-as compared with that obtainable with' so the usual forms cf forced ow feeders of either the reciprocating plunger or the vacuum-pressure type-for the joint purpose of increasing the j from the suedreneertn chamber to the mam supply body while under the ccinplemental action 45 of `the periodically applied airgpressure.

These 'and objectsV which will be hereinafter made readily apparent to'those skilledfin this particular art are accomplished by means oi the invention described in the following speciflcation and illustrated inf-the accompanying draw-l ings,wherein: s

\ Figure 11s s vertical recaen taken through the yiiow orifice of an apparatus for carryingout my invention;

oi the stream after air pressure has been applied to the molten glass in the sub-forehearth to expand and stui the gob; t

Fig: VI is a view illustrating the movement of the shear mechaijiismv in severing the stream of glass;

Fig. VH is a vertical section taken through the ge flow orice oianother apparatus for carrying out my invention;

Fig. VIII is a transverse sectional view through the orifice of the apparatus illustrated in Fig.

` g5 Fig. m is a horizontalfsection taken on line IX-m of Fig. VE;

Fig. X is a horizontal section taken on linek X-Xof Fig. VH;

Fig. m is a view in vertical section on the same au line as Fig. and shows that `portion of the apparatus which is above the apparatus illustrated in Fig. VH;

Fig. m is a view in vertical section of a shear mechanism for severing the continuous owing stream at the point of reduced cross section;

Fig. m is a horizontal section taken on line m-m oi' Fig. mi

Fig. m is a projection of the cam surfaces employed in closing the shear blades;

@a Fig. XV is an enlarged view illustrating a detail of the shear closing mechanism;

Fig. XVI is an enlarged sectional view illustrating the valve controlling the operation of the shear mechanism;

Fig. XVH is a view in vertical section taken on a longitudinal plane through the ilow orice of another apparatus embodying amodication of my invention; the mechanism for shearing the stream being in elevation and illustrating the position of the parts at the-time the -blades start the severing action;

Fig. XVHI is a view in horizontal section taken on line Kvm- XVIII of Fig. XVII; y

Fig. m is a'horizontal sectional view taken on line m-m of Fig. XVII; and

Fig. m is an enlarged sectional view illustrating apparatus for controllingl the operation of the shear mechanism illustrated in Fig. XVII.

Referring to the formlof construction shown so in Figs. I to V., inclusive, i indicates a forehearth extension or boot of the usual type which extends out' from the iront of a glass melting tank or furnace (not shown) and is equipped with burners in the usual manner. The forehearth Il 65 terminates at its outer end in a sub-forehearth il having a iioor I2 which is located a substantial distance `below the bottom. of the iorehearth. Extending upwardly from the iloor l2 of the subforehearth, is a refractory member Il having 'lo therein a chamber Il and a longitudinally extending passageway Il which -is shown parallel to the chamber I4 and in communication therewith adjacent the bottom ot the member through a port IB. The member I3, as shown. is provided,

75 intermediate of its ends, with-a anged portion ademas i3d which is engaged by ledges i'i-Il that project inwardly from Ythe sidewalls of the forehearth ill, and forma partial roof for the subforehearth chamber. These ilange and ledge portions iSa-ii, form, with the member I3, a glass 5 retaining darn at the front end of the main i'orehearth chamber and prevent -the molten glass from ilowing into the sub-forehearth enclosure, except through a valve controlled port I8 Awhich leads to the upper end of the passageway I5. As a result of this construction, the molten glass in Athe forehearth i0 ows by gravity through the opened port i8 into the passageway I5 and thence through the port iinto'the chamber it, which is open at its lower end and in con stant communication with a delivery orice is in a block 2li thatis mounted in` thefoor i2 'of the sub-forehearth. The area. ofthe passageway i5 is considerably greater than the area of the orifice iS, and, due to the height of the column fof glass in the passageway i5, a. static head is maintained which not only causes the molten glass to ilow in a continuous stream through the Y orifice i9 but also to rise to a substantial height in the chamber it.

The' member i3 is positionedv as a unit in the sub-forehearth and is held in place therein by a block 2i which ts over the top of the member and forms a part of the roof of the main forehearth it. The block 2iis held in place by a plate 22 which is bolted to the metal frame or jacket 22a that supports th'e entire i'orehearth and sub-forehearth assembly. To prevent the escape of hot gases of combustion, the space between the lower .face of the plate 22 and the adjacent surfaces of the forehearth roof is lled with a soft packing 22h of asbestos, or asbestos clay cement, which seals the opening around the edges of the block 2i.

In order to periodically accelerate the gravity how of molten glass through the oriiice i9, and thus produce a stream having a regularly recurrent series of enlarged portions'oi predetermined size and shape, an extruding or expelling force is periodically applied to the top of the molten material within the chamber i4, which accelerates theow through the oriilce and swells or expands the stream discharging therethrough.

. To apply such an accelerating'force to the molten glass, in the chamber i4, a. suitable elastic iluid, such as compressed air, is introduced into the chamber i6 at regular intervals, through communicating passageways 25 and 26 in the coengaged members i3 and 2i, which are connected by means of a pipe 21, a passageway 28 in a'valve housing 29 anda pipe 30 to a suitable source of air under pressure. The admission ofair to the interior of the chamber Il is controlled by a valve 3l which is mounted in lthe housing 29 and normally closes the passageway 28. The valve 3| is held in its vhclosed position by a spring member 32 which is positioned between the top of the housing 29 and a collar 3l that is mounted on the upper end of a stem 3l `extending upwardly from the valve 3l. The valve 3| is periodically opened by a cam 36 which is mounted in a shaft 31,- and which engages a cam roller l! carried 'by` the valve collar II, vThe 'shaft I1 is mounted in bearings ll on a forked arm support 3l that extends upwardly from the roof of the torehearth Il and is continuously driven in a clockwise direction by a suitable motor (not' shown).

From this construction, it is apparent that the cam 8B periodically depresses valve stem 34. opens 7l I (the conduit Y30) 'which forces the glass therefrom and accelerates its flow through the orifice I9. To reduce the pressure in the chamber. I4 when the valv 3l is closed and permit the molten glass to iiow rapidly into and ll the chamber I4, a passageway 40, communicating with the pipe 21, is provided in the housing 29, which is lopen to atmosphere, or if desired may be connected to a vacuum when the valve 3I is closed. When the valve 3l is opened to admit compressed air into the interior of the chamber I4, the passageway 40 is closed .by the cylindrical extension 4I of the valve 3 I.

In order to obtain the full effect of the accelerating pressure in expelling the molten glass in the chamber I4 through the orice I9, and prevent it from being forced back through the passages I6 and I5 into the `forehearth I0, a plunger valve is reciprocably mounted in the upper part of the passageway I5 and is adapted to be lowered to close the port I8, when the interior of the chamber I4 is connected to the source of compressed air, and raised to open the port when the chamber is connected to atmosphere. The plungercomprises a refractory plug d5 which is supported on the Banged head t6 of a rod El the upper end of which is bolted to a metallic sleeve 138. The sleeve d8, which is made of a suitable high heat resisting alloy is slidably mounted in a graphite bearing@ positioned in the upper end of the passageway I5 and is connected, through the rod il and coupling 'Sii to a rod 5i which is slidably journaled in a cross bar 52 at the upper end of the forked support 3d.' To raise the plunger 45 when the valve 3i is closed and the chamber I@ is open to atmosphere and permit the glass in the forehearth to flow through the port I8, the upper end of the rod 5I above the crosshead 52 is provided with an adjustable nut 53 which is adapted t`o be engaged by the slotted encll of an arm 5d which is carried by the shafft 55 journaledin the support dit. The

arm 5 carries a roller 56` which rides on a carri 59 are threaded on the rod @l1-for limiting they downward movement thereof.

In order to maintain the glass in the passage way I5 and chamber Id at the desired working.,-

temperature, the outer surface of the member I3 is spaced from thewalls of thesub-forehearth `to form therebetween a heating chamber 6d, into which combustible fuel is introduced through nozzles 6I extending through ports 62 in the walls of the sub-chamber II. Thenozzles Si' Yare connected to a pipe 63 leadingto a suitable and independent source of fuel. y .y

To utilize the products or gases of'combustion for the purpose of heating the glass in" the foreyhearth,4f-and also to avoid the use .of special.'- ehimney lues for conducting away .these burner gases-the upper end of the chamber @d isv placed in communication with the main forehearth chamber I0 (as yshown in Fig. III) :and the gases passing into this enclosure are conducted back into the main tank chamber through a window opening 64 in the baie wall or gate 65, which controls the flow of glass from the furnace, from which they are discharged through the furnace stack.

In Fig. IV I have shown another means for maintaining the glass in the sub-forehearth at any desired working temperature. In this modication an electrical heating element 10, which is connected to a suitable source of current, is positioned in the heating chamber 60, and may be controlled, in any suitable manner, for the purpose of maintaining the glass in the delivery boot in the best condition for operation.'l

When the apparatus shown in- Figs. I-V, inclusive, is in operation and the chamber I4 cony nected to atmosphere, the cam 51 is in engagement with and holds the arm 54 and the plunger 45 in their raised position. Glass is then owing under the influence of gravity from the forehearth through the port I8 into the passageway I5 and is discharging from the orifice I9. Since the area of the passageway `I5 is considerably greater than the area of the orifice I9, and since a column of glass is always maintained in the passageway I5, the glass passing through the port i6 is under such a static head pressure as will cause it to flow into andrapidly rise in the chamber Id as well as to ow through the'orice i9 in a continuous stream. When the glass in the chamber It has reached a predetermined level, the cam 5l releases the arm 54 and the plunger $5 is allowed to drop due to itsy own weight, and close the port I8. At the same time the cam 36 depresses the valve stem 34 and opens the valve 3i admitting compressed air linto the chamber it to accelerate the ilow of glass through the orice i9. This accelerated flow expands or swells the stream owing through the orice and since the port i8 is closed, theglass in the passageway I5 is prevented from being yforced black into the fcrehearth I0. After the glass has been subjected to the accelerating force for a predetermined time, the cam 3 6 releases the stem 3e and permits the spring 32 to close the valve 3i and connect the interior of the chamber :le to atmosphere. At the same time the cani 5'l`raises the arm 5t and the plunger 65 connected thereto, and opens the port I8 so that glass is again flowing into the passageway I5. Y

From this construction it isapparent that as a resultvof maintaining a largev quantity of glass in the passageway'i, there is always a continuous flow through the orice under the influence of gravity and at regular intervals, this iiowis sub jectedto a supplemental expulsion force, which acts to accelerate the gravity ow; `and vasa result, a continuous pulsatingv discharge isrproduced at alternately accelerated v,and decelerated velocities of ilow. The iiow of glass thr'ough'the Aoriiice is never arrested-or retarded, butrdue to the decelerated velocity of flow,-that is, the velocity of the ow-underthe inuence of gravity alonethere is a .natural necking"'of kthe glass Y which produces la' stream `ofregu1arlyf recurrent enlarged and reduced'se'ctiorisl of 'predetermined shape andr size. Further, [by having the Vglass abovethe oriilce under 4av relatively high 'static head the Agravity flow is lconsiderably''faster than inffthe ordinary type.' of ynatural yowfeeder in which the glass isnunder a relatively's'mll static head pressure.

win rigs.vn1,'ix,'x, and In, r have shown another form of apparatus fpr carrying fout myy improved method of feeding a stream ofmolten gg glass at a high rate of speed and in the shape of regularly recurrent series of enlarged sections.

" In' this construction, 80 indicates the forehearth extension which extends out from the front f .a glass melting furnace or tank and terminates in `a sub-forehearth 8| on the outer end thereof. The oor of the sub-f orehearth which is locatedV a substantial distance below the bottom of the which is engaged in recesses 80a in the thickened side Walls at' the front end` of the main forehearth. 'I'he upper end of the sleeve 84 is also provided with a notch or gate at its rear or furnace side to permit the glass to flow `from the forehearth to the delivery orifice 83.

In order to control Vthe flow of glass through the gate 85, a refractory bell member 86 having a chamber 81 therein is reciprocatably mounted in the forehearth assembly 80--8| with its lower end extending into the sleeve member 84. The external diameter of the member 86 is substantially smaller than the internal diameter of the sleeve 84, so`that van annular passageway 88, is formed therebetween, which is of considerably larger area than the area of the orifice 83. As a result of this difference in area, the glass flowing through the passageway, 85, will be delivered to the interior of the sleeve 84 at a higher rate of speed than it can be discharged through the orice 83, and will therefore flow into and rapidly rise in the chamber 81. f

When thev molten glass has reached the desired level within the chamber 81, the member 86 is raised to bring an annular shoulder 89, on the outer surface of the bell 86, into close proximity to an inwardly projecting annular shoulder on the inner surface of the sleeve 84 for the purpose of throttling the passageway 88 and substantially arresting any flow of glass through the passageway 85.

In order to prevent the refractory sleeve 84 and the refractory member 86 from chipping and wearing away, I prefer to cover the shoulders 89 and 90 with liners 9| and 92. which may be made of a suitable non-corrosive and high `heat resisting metal or alloy.

For the purpose of permitting the member 86 to be periodically raised andlowered, the reduced upper end thereof is extended through an opening in a block 93 (which forms a part of the roof of the *main forehearth), and is clamped to the lower end of a collar 94 that is slidably mounted -in a bearing 95 on a crosshead 98, which extends between upright posts 91 that support the forehearth and sub-forehearth on the front of the main furnace or tank.

VThe upper vend of the collar 94 is secured to the end of a tubular rod 98 with set screws .99 (see Fig. XI) and the upper end of this rod is fastened to a piston |00 which is slidable in a.

. cylinder |0|, thatis supported by a crosshead |02 mounted on the posts 01-91. The lower end of the tube 98 is connected, by the right and left hand coupling |04; to the upper end of a tube |08 .extendingthrough the member 86 and-opening into the chamber 81. To move the piston |00 up raising and lowering the member 06compressed of the cylinder through pipes |05 and |06. leading to a double-action timer valve cylinder |01 that is continually supplied with compressed air through a pipe i08 leading to a hollow mandrel |09 that is connected to a suitable source of motive uid by a pipe H0. The timer valve assembly is of the usual well known piston type, which is operated by a cam that is secured to a cam shaft H3; and is driven at a controllable speed through a worm gear ||4 on the cam shaft, and a 'worm |5 on the armature shaft i6 of a suitable motor M.

In order to acceleratethe flow of glass through the orifice 83 at the time when the member 86 is in its raised position, an external expelling force is applied to the molten glass in the chamber 81 to periodically supplement the action of gravity in expelling the glass therefrom'through the orice, and to thereby swell or stu the owing stream to form a series of expanded and preshaped mold charge sections. This supplemental extrusive action is conveniently obtained by providing the piston |00 with apassageway |1 which communicates with the interior of the tubular rod 98, and through which compressed air may be delivered to the chamber 81 where the connected members 86-94-,98-"30 have been raised by the admission of the motive ilow to the lower end of the cylinder lill.

When the bell member 86 is lowered, the passageway ||1 is closed by a valve |2| which is adapted to engage and seat against the lower side of the piston |00 when the latter is moved to its lower position to open the passageway 89. This valve |2| is attached to a stem |22 which is threaded through tne hub of another valve element |23 that is adapted to control a port opening in the lower head of the cylinder |0|, and isslidably mounted in an adjustable screw |24 that is carried by a bracket |25 on this head. v The connected valve elements |2||23 are normally held in their raised position (shown in Fig. XI) by a coil compressing spring |23a which is inter= posed between the `valve |23 and the upper end of the screw |24. When the pistonV |00 is moved downwardly in the cylinder for the purpose of opening the passageway 88, the valve |2| seats over and closes the passageway I1; and if the valve engages with its seat in the piston before the latter reaches the lower limit of its travel, the further movement of the piston moves the valve assembly downwardly against the action of the spring and opens the lower end of the cylinder |0| to the atmosphere.

When the member 86 is moved toits lowermost position and the passageway 80 is open, a direct communication is also established between the bell chamber 81 and the atmosphere, through a port |`|8 in the side of the tubular rod 98, and a port ||9 in the lower cylinder head and the'air in the chamber 81 is the'n permitted to escape through a passageway |26 which leads from the port I9 to the external air or to a suitable source of air in the said chamber when the glass has 15.-

reachedV a predetermined level therein, and thus preventing the further flow of glass to the interior of the bell. This is accomplished by providing a disc valve 21 which is disposed in the passageway |26 and which is adapted to close vthe said passageway when the glass in the chamber approaches the desired predetermined level. 'I'he valve |21 is normally held in its open position to allow the free discharge of the air from the chamber 81, when the ports ||8 and ||8 are first brought into communication with each other, by means of a weight |28, which 'is mounted on a valve stem |29 extending upwardly v from the disc |21, and which is suiiciently heavy to overcome the lifting tension of a spring |30 positioned beneath the disc |21. The upper end of the valve stern |28 extends into an opening |3| .in the core of a solenoid |82, one terminal of which is-connected, by a heavily insulated wire |38 and the battery B to a terminal |34 extending into the molten glass adjacent the bottom of sleeve 8l, while the other terminal is connected, by means of the metal parts |20, 98, and |03, with a terminal |35 extending downwardly from the lower end of the tube |03. When the molten glass has' risen in the chamber 81 suillciently to come in contact with the terminal |35 (Figs. VII and VIII) an electrical circuit is established which energizes the solenoid and lifts the weighted armature |28 of the disc valve |21 to close the passageway |26. The closing of this passage traps a quantity of air in the chamber 81, which is compressed by any further rise in the molten glass therein; and thus establishes a 7this downward movement of the valve |21'takes place after the piston rod 98 has been lifted to throttle `and substantially close the glass supply port 88; but as will be hereinafter Apointed out, the valve |28 may be opened at any time regardless of the position of the ports ||8 and H0 to each other.

In order to maintain the glass in the member 80 at the desired working temperature, the outer surface of the member is spaced from the inner surface of the sub-forehearth 8| to form therebetween a combustion chamber |36, into which a combustible fuel is introduced through nozzles I 31 which lead from' a suitable fuel line |38 and extend through openings |39 in the .floor and side walls of the sub-forehearth. The hot gases of combustion pass upwardly in the combustion chamber |36 around the member 80 and into the forehearth 80, as shown in Figs. VII, VIII, and X; and are then dischargedinto the main glass furnace through an opening |40 in the movable baille block IM which controls the flow of glass from the tank into the forehearth.

The baille block |4| extends through an openv ing in the roof of the forehearth 80, and is sup- To prevent the hot gases from escaping from the forehearth, adjacent the member 88, the roof block 88 is provided witha depending annular flange |05 which' vprojects downwardly into the molten glass and forms therewith a liquid seal that prevents the'gases of combustion within the forehearth chamber from coming in contact with the member 86.

The operation of this construction is as follows: With the parts in the position shown in Fig. VII, molten glass is flowing, under the influence oi gravity, through the notch or gate 85, into the passageway, 88, and is being discharged through' the delivery orifice 83. Since the area of the passageway 88 is considerably greater than the area of the orice, and since the static pressure in the passageway is relatively high, the molten glass also flows' into and rapidly rises in the chamber 81. Wheny the glass reaches a predetermined level in the chamber 81, the cam is adapted to actuate the timer valve in the cylinder |01, and connect the pipe |06, leading to the underside of the piston |00, to the source of compressed air. As the piston movesupwardly the member 86 which is connected thereto is also raised and the shoulder 89 is moved into close proximity to the shoulder 80 thereby shutting 0H the flow of glass through the passageway 88. As the piston |00 is being moved upwardly, the port ||8 is moved out of registration with a port H9; and at the same time, the valve |2| is unseated to permit the compressed air in the cylinder |0| to ilow through the passageway ||1 into the chamber 01, and subject the glass therein to an added force which materially accelerates the natural gravity ilow from the delivery orifice 83, and swells, or increases the volume of the issuing stream.

If, however, the glass in the chamber 81 should' reach the predetermined level before the cam is in position to connect the underside of the piston |00 with the source of compressed air, the glass rising in the chamber will come in contact with the terminal |35 and establish an electrical circuit which will energize the solenoid |32 and close the Valve |21 whereby a quantity of air will be trap'ped inthe chamber 81 and will prevent the glass from rising materially above the rst contact level. A`s soon as the piston |00 has been raised and the level of glass in the chamber drops or is forced out of contact with the terminal |35 the solenoid |32 is deenergized and the passageway |26 is again opened. But, it is obvious that the solenoid may also be deenerglzed, and the passageway |26 opened at any time, regardless of the position of the cam by means of a break switch S in the battery line |33.

When the required quantity of glass has been forced out of the chamber 81, the constantly revolving cam acts to again operate the timer valve in the cylinder |01, and connect the pipe to the source of compressed airthereby admitting motive fluid to the top of the cylinder |0|and concurrently connect the pipe |06 to an atmospheric vent port. The superior pressure on the upper side of the piston |00 will then move the connected members 98-94 downwardly and reopen the glass supply passage 88. As some point intermediate the beginning and end of its downward stroke the piston engages the Valve |2| and closes the passageway ||1 which shuts 0E the flow of air from the lower end of the cylinder |0| to the interior of the chamber 81. As the piston |00 continues its downward movement the ports ||8|`|9 are brought into registry and the interior of the bell chamberv8`| and is then directly connected to the atmosphere or to a source of subatmospheric pressure (as previously indicated) and glass is permitted to ow freely into the said chamber, either under the influence or gravity alone, `or under the joint inuence of gravity and a partial vacuum.

From this construction, it is apparent that the molten glass Within the chamber 0l is not subjected to the full effect of the supplemental extruding or expelling force until the passageway 88 is substantially` closed; and that when this supplemental force is applied, the glass in the chamber is prevented from being forced back into the pool of glass within the forehearth; and the resultant flow through the delivery orifice is greatly increased. Also, since the interior of the chamber 0l is not directly connected to atmosphere or to a vacuum,-by the registration sageway |26 has been fully opened, there is always a gravity flow through the orifice 83 which is not, at any time arrested or retarded, but which is periodically'accelerated by the'supplemental expelling force; and a stream of alternateenlarged and of reduced cross sectional areas is produced which is 'adapted to be severed at the points of reduced cross sections to form individually preshaped mold charges or gobs.

It' is also apparent that the alternate admission and escape of air through the pipe connection IUS- which acts to raise the pistonbell assembly, M30-86, and also control the flow of motive fluid to the bell chamber-can be controlled by the throttle valve llliial (Fig. XII); so as to regulate both the speed of lift and the speed of drop of the movable members; and that the extent or range of this movement may also be regulated by the stop screw |0|a in the upper head of the cylinder |0|, and by the adjustable lock nuts i0 lb on the upper end of the piston rod 98. It is further possible to limit the expelling pressure on the glass in the bell chamber-independently of the pressure in the supply line ||0by means of the relief valve |23 which can be adjusted to open at any predetermined pressure by turning the sleeve screw |20 and thereby changing the tension of the spring |23a. It is also possible to ch'ange the point at which the expelling pressure is first applied to the glass by moving the valve element |2| up or down with respect to the valve element |23; this being accomplished by turning the valve stem |22 in the threaded hub of the Valve |23.

To sever the stream at the point of reduced cross sections to form a series of successive mold charges of predetermined shapes and sizes, a suitable high speed shear mechanism |50 (Figs. XII, XIII, XIV, XV, XVI, XVII, and XX) is mounted below the sub-forehearth. This shear mechanism is preferably of such construction as to effect the severance, by a concurrent transverse and axial movement of the cutting elements, so as to avoid any tendency to interrupt or retard the free downward flow of the material, and likewise prevent any piling up and chilling of the molten glass in the shear blades. The shear mechanism here illustrated is supported, as a whole, on a frame or base plate |5| that has vertically disposed side plates |52|52 attached to one end of the frame (right hand end as shown in Fig. XII) and whose upper ends are journaled on the hollow mandrel |09, which is located above andrto the left of the portions of the plates secured to the frame |5I. The mandrel is, in turn, supported in brackets ISS-|53 on the upright rods or columns 91-91. 'I'he frame |5|` also carries the motorM and the weight of the motor M, the shear mechanism |50, and the other elements carriedthereby is so distributed thereon that the frame has a tendency to turn about the mandrel |00 in a clockwise direction and move the shear mechanism |50 toward the bottom of the forehearth 80. This movement ofthe frame |5i, in a clockwise direction, is resisted and counteracted by a spring |98 which is positioned between the forehearth and the frame |5i, and which is so adjusted that it tends to turn the frame in the opposite direction; Movement ofthe frame |5| by the spring |98, however, is prevented by an eccentric hub |09 on a gear sleeve ld-|10 which bears against a xed roller |96. The purpose and function of this construction Will hereinafter be more fully explained.

The shear mechanism |50 comprises a pair of opposed shear blades ld-|54' of either the straight edge form er the usual cats eye form, which are mounted on' cross bars, |55-|55' whose ends are rigidly secured in the upper terminals of the opposed pair of arms ISS-|56. The lower ends of both sets of arms are coaxlally journaled on stub shafts IS7-|51' that are rigidly supported in diametrically opposed portions I 58-|58 of an annular sleeve |59, which is rotatably mounted on a ball bearing |60 positioned between the sleeve and an inner cylindrical member IBI, which is secured to the base plate ISI.

The shear blade members IBA-|54' are normally held in their open position by tension springs |02-I62 which are attached, at their upper ends to the arms |56|56', and are connected, at their lower ends to the sleeve |59; and when in their open position the outer portions of these blades are received in segmental troughshaped boxes IBS-|63', one of which is supported on a crosshead |64 that extends between the brackets |52, and the other of which is supported on a bracket Nida that is attached to the frame of the sub-forehearth 0|. These boxes IES-|63 may be filled with a suitable liquid such as oil, which will serve both as a lubricant and as a cooling medium for the cutting elements.

The two cooperating pairs of shear blade arms, ISE-|56 and |56'-|56-which `are pivotally mounted on the common stub shafts IST-|51'- are respectively connected, at their lower or inner ends, by curved crossheads iBS-|65' of T- shape cross section; and each of these crossheads is provided with a depending finger (marked |66 -|66, respectively), which rides on a corresponding cam face |61-I61', that are formed on the inner surface of the stationary annular member |6I; so that as the sleeve |59 is rotated, the ngers |66, |66 Will ride over these cam surfaces and rotate the connected arms .about their pivot supports, to thereby first move The del pose of actuating the shear blades in the manner f Ans , 2,141,4a outer surface of the 'sleeve |59' and isprovided with a bevel gear |19 which is engaged with a pinion |1| on the end of a shaft |12. The shaft y|12 is journaled in a bearing |13 carried on the frame |5|, periodically rotate the sleeve |59by a friction clutch assembly ||18, one element (|15) of which is slidably keyed onthe shaft 12 while the other element (|16) is secured to the end of the continuously driven motor shaft IIS. V

The element |15 of the clutch is moved toward and away from the element |16, to respectively engage and disengage theclutch, by 'abell crank lever |11, which is pivotally mounted on the frame |5|, and has the upper end thereof coupled to the clutch. element |15, by thel usual collar connection. The other arm of this lever is exibly coupled to the lower head of a metallic bellows |18 and is also engaged by a spring v|19 which is mounted in a recess |90 in the frame. 'Ihe bellows |18 is normally held in its expanded position to hold the elements of the clutch in disengaged position by compressed air, which is introduced therein through a passageway |9| that is connected, by a pipe |82, to the cylinder |93 of a timer valve assembly which is supplied with air through the pipe |08.

The detail construction of the last-mentioned timer valve member-which serves to periodically engage the elements |16 and |15' 'of the clutch,is shown in detail in Fig. XVI. It comprises a double-headed valve element lat-|98 which is adapted to be moved in one directionto seat the head |84, and shut oil the supply of air to the bellows |18, and at the same time unseat the head |98 and thus connect the bellows to atmosphereby a cam |9| which isA keyed to the continuously revolving cam shaft ||3 (supra). and which engageswith a cam roller |90 on the valve head |08; and is adapted to be moved in the reverse direction (to seat the valve head |89 and unseat the head |84) by a spring |81 which is interposed between the ported partition |86 and the head |88. As a result of this construction, it is seen that the periodic engagement of the raised portion of the cam |9| with the roller |90, momentarily closes the connection between the compression air line |08 and the pipe |92, and simultaneously opens the vent port |99, whereby the delivery of air to the bellows is shut oil and the interior of the bellows is connected to atmosphere permitting it to collapse. On the collapse of the bellows- |18, the spring |19 rotates the bell crank |11 and moves the clutch element |15 into engagement with the clutch element |15. As soon as the clutch elements are engaged, the sleeve |59 starts to turn and the fingers IE6-|66 immediately start to ride up on the cam surfaces i1-|91 and advance the shear blades toward each other.

To prevent the elements |15 and |19 of the clutch from being moved apart or disengaged until the sleeve |59 has been turned through one complete revolution, and the shear elements have thus been closed and reopened, an auxiliary l'valve |92 is interposed in the passageway |8| for automatically closing the latter at the start of 4rotation of the sleeve, and keeping it closed until vthe sleeve is stationary (i. e., when the clutch elements |15|16 are dis'engaged) the valve |92 is held in its open position by the engagement and is intermittently driven to.

oi this cam with the outer end of the valve stem |99. But, as soon as the sleeve |59 starts to rotate, the cam |915 is moved out of contact with the valve stem |93 and the valve |92 is closed by the backing spring |95; and it remains closed until the sleeve has nearly completed its revolution, at which time the beveled end of the cam |94 again engages the valve stem |93 and moves the valve |92 to its open position, thus reconnecting the bellows |18 with the cylinden |83'. Since the valve |94 is only momentarily closed by the cam |9|, compressed air is now again admitted to the bellows |18, and the bellows are immediately expanded, to return the bell crank` |11 to its initial position (as shown in Fig. XII) and thus disengage the clutch elements |15-|19. To stop the rotation of the sleeve |59 as soon as the clutch elements are disengaged, the slidable element |15 of the clutch, is adapted to engage with a fixed collar |15a. on the shaft bearing box |19, thereby applying a brake to the shaft |12 and bringing it to rest in such position that the ngers ISB-|96' drop into the depressed portion of the cam faces IBL-|51' (see Fig. XIV) and permit the shear blades to be retracted by the springs "i2-|62.

In order to obtain a combined axial and transverse movement of the shear blades ld-|54 during the severing operatlon,. I have provided a roller |96 which is mounted on a stub shaft |91 that is carried by the crosshead |69, and which Qis so positioned on the crosshead that it is located in the arcuate path of travel of the eccentric hub |69 on the gear sleeve Mit-|19. When the connected sleeves |99|59 are rotated, the frame |52 is rocked on its mandrel support |09, by the engagement of the revolving eccentric hub |99 with the fixed guide roller |96 and by the action -of the spring |93 which is attached to the bottom of the forehearth and the top of the frame |5| and which holds the moving member |69 against the xed guide roller |96 due to the fact that it is positioned in the arcuate path of travel of the hub |69. To regulate the tension of the spring, the lower end thereof is secured to a threaded eye-bolt |99 which extends through a bracket 290 on the frame. A nut is provided for moving the bolt |99 relative to the bracket.

'I'he eccentric hub |98 is so shaped, and so positioned in relation to the cam surfaces ISL-|61 that, as the sleeve |59 revolves, the outer end of the frame |5| will lrst be moved upwardly toward the bottom of the forehearth and will reach' its highest point at the time when the blades are just starting to enter the stream of glass (see dotted lines in Fig. XII). As the movement continues, the swinging movement is reversed, and the outer end of the frame moves downward to its original position; so that the blades move with the stream during the severing operation (as shown in Fig. VI). The cam surfaces |61-|61' are also preferably so shaped that the time of contact of the cutting elements with the stream, the revolving shear assembly will revolve through at least one half a revolution; that is to say, the movement of the shearblades ISG-|55 from the full line position tothe dotted line position of Fig. XII Will be effected during the first half of the revolution of the sleeve |59; and, the cutting or severvalve cams I|| and |9| are preferably so adjusted that the stream will be severed at the points of reduced cross sections between the enlarged portions produced by the periodic application of the supplemental expelling pressure to the glass above the delivery orifice; i. e., at the points where there is a natural necking in the stream due to the decreased velocity of delivery, under the action of gravity alone, when the supplemental force is removed.

To recapitulate: When the cam |95 engages the roller IML-thereby closing-the valve |84 and opening the valve |88-the bellows I'I will collapse; the spring |19 will engage the clutch elements I'I5 andI'IB; and the sleeve |59 will begin to move.

As the sleeve |59 starts to rotate, the fingers ISG-|68 ride up on the cam faces ISI-|61 and advance the shear blades ISG-|54 toward each other. At the same time, the engagement of the eccentric .sleeve |88 with the roller |96 causes the frame carrying the shear mechanism to swing about the mandrel |89 and to lift the advancing l v blades toward the bottom of the sub-forehearth.

As the blades start to enter the stream, the frame carrying the shear mechanism is swung downwardly so that the blades travel with the stream during the time they are in engagement therewith.v The cam faces ISI-|31' are so preferably shaped that the final closing movementduring which the blades are in contact with the glass-requires at least one half of a complete revolution of the sleeve |59. As soon as the cut has been completed, the fingers IBG-|63 drop into pockets in the cam faces IBI-|81 and permit the shear blades to be quickly retracted by the spring members IGZ-|62 and returned to their open position. When the sleeve |59 has been turned through approximately one complete revolution and just before the shear blades are retracted'as stated, the cam dog |94 engages the valve stem |93 and unseats or opens the valve |92, thereby readmitting compressed air to the bellows |78 and disengaging the clutch elements I'I5 and |18 to stop the rotation of the shaft |12 and the sleeve |59. When the next gob or'charge is to be severed fromthe stream, this cycle of operation is again repeated.

In Figs. XVII, XVIII, XIX, and XX, I have shown another embodiment of my uni-directional force feeder, and also a slightly modified form of rotating and dropping shear mechanism. In this third exemplification of my improvements, the molten glass is contained in a forehearth 2 I0 having at the outer end thereof a sub-forehearth 2| I, the floor (2 I2) of which is substantially lowerthan the bottom of the main forehearth. Positioned in the sub-forehearth 2I| and extending upwardly from the floor thereof is a hollow refractory member 2I3 which is supported intermediate of its length on flanged ledges 2 I4 extending outwardly from the side walls of the main forehearth. The refractory member 2 I 3 is positioned over an orifice 2 I5 in the bottom of the sub-forehearth and is provided with an inner sleeve ZIB which is spaced therefrom to form an annular passageway 2 I 1, whose cross sectional area is substantially greater than that of the orice 2|5. The molten glass in the forehearth 2I8 ows by gravity through ports 2 I8, in the side wall of the member 2I3, into the passageway 2Il, and then through the ports 2I9, in the bottom of the sleeve 2| 6, and is discharged in a continuous stream through the orifice 2|5. Since the orice 2I5 is of materially smaller area than the passageway 2| 1, the flowing stream of glass will also tend to "back up and rapidly rise in the chamber in the sleeve 2I5 under the effect of the gravity head of molten material in the upper forehearth chamber 2 I 8. Y

In order to periodically accelerate the gravity flow through the orifice, a refractory plunger 22|! is reciprocably mounted within the. sleeve 2I8,

Aand is adapted to be periodically depressed to exert a supplemental extrusion forceon the glass in the interior of the sleeve. The plunger 228 is mounted on a rod 22|, and is connected at its upper end to a hollow sleeve 222 made of a suitable high heat resisting alloy. The sleeve 222 extends through an opening in a roof block 223 and is slidably engaged by a graphite bushing 224, which is mounted in a housing 225, that is supported on the roof plate 226. The upper end of the sleeve 222 is detachably coupled at 227, to a rod 228 which is reciprocably mountedin the front wall of a box shaped bracket frame 229, that is carried bythe side posts 238 of the forehearth assembly.

When the flow of glass through the orifice is to be accelerated, the plunger22|l is moved downwardly `to force the glass in the interior of the sleeve Vthrough the orifice and thereby swell the gob by increasing the rate of iiow through the orifice. In the construction here illustrated, the plunger is actuated by a forked lever member 23 I, where ythe outer end is pivotally connected to a vertically adjustable collar on the plunger rod 228, and whose inner end is journaled on a stud bolt 232 that extends through a slot 233 in the lever 23| and is clamped in any desired position in a slotted extension of the rear wall of the bracket frame 229. The lever 23| is periodically forced downwardly to depress the plunger 220, by a cam 234 which is secured to a continuously revolving cam shaft 235, and which engages a roller 236 mounted between the forked arms of the lever. The cam shaft 235 is driven through a suitable worm gear (such as is shown in Fig. XIX), which is' engaged lby a worm 238 on a continuously driven motor shaft 239.

In order to prevent the glass in the chamber 2I'I from being forced back through the ports 2 I 8 into the forehearth when the plunger 220 is moved downwardly, I provide a suitable gate 248, of refractory material, which is positioned in front 'of these ports, and is automatically moved to sabstantially close them, at or about the time when the plunger starts its downward movement. In the construction here shown, the upper end of the gate 240 extends through an opening in the roof of the forehearth, and is suspended on a rod 24| which is embedded in the body of the gate and is clamped to a metallic sleeve 242 formed of a high heat resisting alloy. The sleeve 242 is slidably mounted in agraphite bearing 243 in the housing 225, and is detachably coupled, as at 244, to the lower end of a shaft 245, which extends upwardly and is reciprocably guided in a cross bar 246 that forms a part of the box shaped frame 229. The upper end of the rod 245 is flexibly coupled to the outer extremity of a lever 241, which is pivotally mounted on a cross shaft 248 that is carried by the frame 229. The gate 240 is normally held in its upper position-to permit the molten glass to flow freely from the forehearth 2I8 through the ports 2 I8 into the passageway 2|'I-v-by a cam 249, on the cam shaft 235, which engages a'roller 250 that is carried by a stud bolt bearing 25| on the lever arm 241. 'I'he cam 249 is so shaped and adjusted as* to permit the connected lever-gate intothe rotor chamber through a. pipe 262 leadassembly 241-245-242-240 to drop under its own weight, and cover the ports 2|8, when the cam 236 initiates the downward movement of the plunger 226. y

In order that the plunger 220 will apply a force -to the glass in one direction only and thereby -avoid any retardation or retraction of the ow of the glass through the orifice on its upward movement-such as always occurs in the operation of the present types of sticky plunger feeders-the cams 23B and 249 are preferably so formed and so set in relation to each other that the plunger will remain in its lower position until the gatell ha`s been raised to reestablish the flow of molten glass from the forehearth to the interior-of the sleeve 2|6. will float? the plunger 226 to its raised position;-this upward floating movement being assisted by a weight 252, which is attached to the inner end of the lever 23|, and which can be adjusted so as to counterbalance a part of the weight of the plunger and also assist in overcoming any frictional reiistance to its upward movement.

In order to assist the plunger in expelling the glass during its downward movement, I preferably employ a bearing sleeve which is of somewhat greater diameter than the plunger itself; and when their connected parts are depressed the air which is trapped between the enlarged upper portion of the member 222 and the glass ln the interior of the sleeve 2 I6 is subjected to compression, and this supplements the expulsive action of the plunger itself. In order to avoid any possible rarecation of the trapped air during the reverse upward (floating) movement of the parts, the

V annular space between the plunger and its enclosure, sleeve 2|3 is connected with a passageway 255;, inthe housing 225, which is provided with a. sensitive control valve 256 that will open automatically to the atmosphere when thev pressure within the sleeve drops below a predetermined amount. l

From this construction it is apparent that when the gate 24U is raised, molten glass will flow freely from the forehearth throughthe ports 2id into the passageway 2|'1 and then through the ports 2|9 into the interior of thesleeve 216 and also through the orifice 2|5. Since the area of the orifice is `materially less than the area of the passageway 2|1, and since the glass therein `is under a relatively high gravity head, the glass will quickly rise in the sleeve 216 and float the plunger upwardlyiand as a result,` the plunger does not impart any retarding or retracting force to the gravity ow through the oriilce.

To maintain the glass in the delivery passageways and chambers, at the desired working tempartiture, combustible fuel is introduced into the sub-forehearth through suitable ports 256 by mixing burner 256a that are preferably arranged 4als shown in the cross sectional views of Figs. 'XVIII and XIX, and which are fed by the/fuel pipes251. /The gases of combustion pass tan/ As the level of glass rises in the sleeve, it y ing from the hollow mandrel |69'. The shaft 26| carries the clutch element |16.

The clutch elements are normally held in released or disengaged position by the bellows |18 which is supplied with air through the pipe |82 which in this construction communicates with a port 263 in the side of the hollow mandrel |66'. In order to engage the clutch elements |15-i16 to rotate the sleeve |59 and close the shear blades ld-|52', a valve 265 is positioned in the hollow mandrel ||i9'.and is adapted to be momentarily closed at regular intervals to shut off the supply of air to the bellows |18. 'Ihe valve 265 is normally held in its open or unseated position by the pressure of the ai in the mandrel |09', and is provided with a stem 266 which extends beyond the end of the mandrel, and carries a, disc valve 261 for closing the atmospheric vent port 268 at the outer'end thereof. The projectingend of the stem 266 is connected to one end of a lever 269 which is centrally pivoted on a bracket 216 that forms a part of the mandrel support 211. The other endof the lever 269 carries a roller 212 which is engaged by a face cam 213,.that is carried by a worm wheel 211i. The connected elements 213-6, are rotatably mounted on a stud bolt 215 and are continuously driven from the motor shaft '239, through a worm 216.

The stream of glass is severed into mold charges in timed relation to the movements of the plunger 222, and when the apparatus is in operation, the continuouslyrevolving facev cam 213 is adjusted to close the valve 265 at or about the time when the plunger 220 has reached the end of its own stroke and the gate valve 266 has been raised to permit the glass to ow by gravity into the plunger chamber and float the latter blades towards the orifice and the eccentricv sleeve is so shaped that the blades reach their highestposition as they enter the stream of glass.

Further rotation of the'sleeve |59 completely closes the shear blades and causes them to travel with the stream during the severing operation.

After the cut has been made, the rotation .of the sleeve is stopped by opening the valve |92 which admits compressed airv into and expands the bellows |18.

From the foregoing description it is apparent that I have provided an improved feeder of the forced flow type in which the applied forces act in one direction only; and as a result, there is no retarding or retraction of the flow, in the intervals between such applications. On the contrary,

' a continuous high speed gravity flow is always maintained by reason of the relatively high head of glass maintained in the sub-forehearth; and this flow is preferably accelerated by the application of a supplemental extruding or expelling force that swells the stream to form a regularly recurrent series of enlarged sections that are connected by portions of lesser diameter. But

these smaller sections are not produced by the action of any retardant or retractive forces, but are the result of a natural necking in the glass which is caused by the decreased gravity flow through the orifice, between the times of forced or accelerated ow and by the fact that the depending glass below the orifice tends to pull awayY faster than the gravity flow can maintain the area of the stream or can follow the sag of the depending portion thereof. Since the continuous ow of glass through the orifice is never arrested or retarded, there is no loss of time between the formation of the successive mold charges; and consequently, I am able to deliver these charges at a much higher speed than is possible'with the ordinary types of plunger and air feeders now Vin general use, and also avoid any chilling or other detrimental eect that attends the temporary stoppage or reversal of the outow from the delivery orice.

With the increased speed of operation which is characteristic of the present invention, the continuously flowing stream of glass must be cut in such a way to avoid any-piling up of the material on the shear blades; and I avoid any such action by moving the shear blades downwardly with the stream while ,they are also rotating about the stream as an axis; and as a result of these combined movements, each element of the cutting edges follows a three dimensional spiral path as they pass through the glass. The downward movement of the blades with the stream, during the cutting operation, tends to assist the oncoming ow, and also to accelerate the delivery-of the severed gob to the mold of the forming machine; and the rotational movement of the blades around the axis of the stream, avoids localized lateral pinching and attening out of the soft plastic material, and produces, in consequence, a smoother and more symmetrical cut or severance; and a more rounded, and lessl distorted or deformed contour, of the severed ends.

While I have illustrated several modications of apparatus for carrying out my method of feeding and severing molten glass, it is understood that various other apparatus may be used without departing from the spirit of my invention or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. A glass feeder comprising a receptacle for molten glass terminating in a chamber having its oor disposed substantially lower than the bottom of said receptacle, a discharge outlet in the floor of said chamber,` a member within said chamber and having a passage therein communieating at one end with said receptacle and at thc other end with said outlet for maintaining a column of glass over said outlet, a chamber within said member for accumulating a supplemental supply of glass above said orifice, means for periodically closing the upper end of said passage to segregate said column from said receptacle, and means operating in timed relation to said passage closing means for expelling said supplemental supply from said last mentioned chamber through said orifice while said passage is closed to prevent the displacement of the column of glass over the orice.

2. The combination in a feeder for molten glass comprising` a container for molten glass, a subcontainer having its oor disposed in a plane 4a substantial distance below the bottom of the container and having a flow orifice therein, a

member in said subcontalner having a U-shaped passage therein 'in open communication at its base with said orifice and with one leg communieating with the container, said passage having a substantially greater sectional area than the area of the orice whereby glass is delivered to the orice faster than it can pass therethrough with the excess rising in the other leg of the passage, means for periodically introducing fluid pressure into said passage to expel the excess glass therein through the orice and accelerate the flow therethrough, means for closing said passage, and means foi actuating the pressure Aintroducing means and said passage closing means in timed relation to each other.

3. Apparatus for feeding molten vglass comprising a container and a sub-container having its iioor spaced a substantial distance below the floor of said container, a sleeve member positioned in said sub-container with its upper end projecting above the level, of the glass vin said container, a bushing having an orifice therein mounted in saidsleeve, said sleeve having a portion thereof cut away adjacent said ,container to establishcommunication between said container and the interior of said sleeve, the area of said sleeve being substantially greater than the area of said orice whereby the molten glass is delivered thereto faster than it can traverse the same, means within said sleeve for accumulating the excess glass delivered to the orifice, and

`means for periodically forcing the accumulated excess lglass through said orifice to accelerate the ow therethrough.

4. A glass feeding apparatus comprising a conltainer for molten' glass, a hollow member adjacent the outer end of said container and extending a substantial distance above the molten glass in said container and a substantial distance below the bottom of said container, said member having a portion of its wal'l adjacent the container c ut away to establish communication between the interior of said Amember and said container, a bushing having a ow'orifice ltherein mounted in the lower end of said hollow member, a vertically reciprocating member for closing communication between said container and said member on the upward movement of the reciprocating member, means for reciprocating said reciprocating member, and means for applying an Vexpelling force to the glass in said member.

5. A glass feeding apparatus comprising a container for molten glass, a hollow member positioned adjacent the outer end of said container and extending a substantial distance below the bottom thereof, -said member communicating at its upper end with the container and at its lower v end'with a discharge outlet and having an area substantially greater than the area of the discharge outlet whereby glass is delivered to the outlet faster than it can traverse the same, and a column of glass is thereby maintained above the' l is 2,141,425 having a chamber therein communicating with.D

said outlet and a passageway connecting said container with said outlet and with said chamber,

means for periodically closing said passageway tol shut off communication between said forehearth and said outlet, a reciprocable plunger' extending into said chamber, means for periodically moving said plunger toward the orice tovapply an expelling force to the glass in said chamber, means associated with the plunger for compressing the air in said chamber on the downward movement thereof and supplement the expulsive action of said plunger, and means for automatically connecting the interior of the chamber to atmosphere to prevent rarefaction of the air in said chamber on the upward movement of said plunger.

7. A glass feeder comprising a forehearth for molten glass, a subforehearth depending from said forehearth and having an orifice in the bottom thereof, a sleeve positioned in said subfore-` hearth over said orifice and providing a chamber in' said subforehearth, :means for delivering molten glass from said iorehearth to said chamber, means ior periodicallyv closing ccmmunication between said foreheartlri and said chamber, a plunger reciprocably mounted in said chamber, means for periodically moving said plunger toward' the oriiice to expel the glass in said chamber therethrough, and means associated with said plunger for building up a duid pressure in said chamber on the downward movement thereof.

8. A glass feeder comprising a iorehearth for molten glass, a subforehearth depending from said forehearth and having an outlet in the fioor thereof, a sleeve positioned in said subforehearth and forming a chamber over said orifice, a sleeve surrounding said first-mentioned sleeve and spaced therefrom to provide a passageway therebetween, said last-mentioned sleeve communicating at one end with the material in said forehearth and at the opposite end with said rstmentioned sleeve, means for periodically closing said passageway, a plunger reciprocably mounted in said inner sleeve, means for moving said plunger toward said outlet to expel the glass therein therethrough, and means for connecting the interior of the inner sleeve to atmosphere to prevent rarefaction of the air therein on the upward movement or the plunger.

9. A glass feeder comprising a forehearth for molten glass, a subforehearth depending lfrom said forehearth and having an outlet in the oor thereof, a sleeve positioned in said subforehearth i and forming a chamber over said orice, a sleeve surrounding said mst-mentioned sleeve and spaced therefrom to provide a passageway therebetween, said last-mentioned sleeve communicating at one end with the material in said forehearth and at the opposite end with said rstmentioned sleeve, means for periodically closing said passageway, a plunger reciprocably mounted in said inner sleeve, and meansV for moving said plunger toward said outlet to expel the glass therein therethrough.

10. A glass feeder comprising a forehearth for molten glass, a. subforehearth depending from said forehearth, a vertically extending sleeve in said subforehearth and having a port communieating with the material in said forehearth, a sleeve disposed within said first-mentioned sleeve and spaced therefrom to provide a chamber therebetween, said inner sleeve being positioned over a delivery outlet and in communication with the chamber between said sleeves, means for periodically closing the port in said outer sleeve, and means for periodically applying an expelling iorce to the glass in said inner sleeve.

11. A glass feeder comprising a container for molten glass, a chamber adjacent said container and having a iioor spaced below the bottom of said container, a sleeve positioned in said chamber and communicating at its upper end with the material in said forehearth and at its lower end with a delivery outlet, said sleeve being spaced from the wallsl of said chamber to provide a heating space therebetween, a reciprocable member projecting into the material within said sleeve and-having a cavity therein located below` the level of the glass in said container, means for reciprocating said member, means for periodically connecting said cavity to a source of duid pressure, and means responsive'to the glass level within said cavity for trapping a predetermined quantity of elastic duid therein.

i2. A glass feeder comprising a container for molten glass, a chamber adjacent said container and having a fioor spaced below the bottom of said container, a sleeve positioned in said chamber and spaced from the walis of said chamber to provide a heating space therebetween, said sleeve communicating at its upper end with the material in said forehearth and et its lower end with a delivery outlet, a member projectin'g into the material within said sleeve and c having a cavity therein in open communication with the glass in said sleeve and located below the level of the glass in said container, means for periodically connecting said cavity to a source of fluid pressure to expel the glass therein through the orifice, and means responsive to the glass level within said cavity for shutting o the flow thereto to prevent the overiilling thereof.

13. A glass feeder comprising a container for molten glass, a sleeve communicating at its upper end with the material in said container and at its lower end with a discharge outlet, a, heatingl chamber surrounding said sleeve, a bell reciprocably mounted in said sleeve, means for reciprocating said bell, a shoulder on said bell adapted when in one position to cooperate with' a shoulder on said sleeve and close communication between theA container and the sleeve, and means for periodically connecting the interior of said bell to a source of uid pressure.

14. A glass feeder comprising a container for molten glass, a sleeve adjacent said container and having one end communicating with the material in the container and the other end com- .municating with a discharge outlet, a heating chamber surrounding said sleeve and opening into said container, a bell extending into said sleeve, a shoulder on said bell, means for periodically reciprocating said vbell to move said shoulder into cooperating relation with a shoulder on said sleeve, and close communication between the container and the sleeve, means responsive to the movement of said bell for connecting the interior thereof to a source of viiuid pressure, and means for introducing' gases of combustion into said heating chamber to maintain the glass within said sleeve atq the desired working temperaure..

l5. A glass feeder comprising a forehearth having a. glass compartment and a' chamber, the

' bottom of said chamber being located a substantial distance below the bottom of the glass compartment and having an orice in the bottom ..thereo1', a member in said chamber having a sublivered to the orice faster than it can traverse,

the same with the excess rising in'the other leg of the passage, means for closing communication between the passage and the glass compartment of said forehearth, and means for applying an expelling pressure to the molten glass contained within one leg of such U -shaped passage..

16. A method of feeding molten glass from al container through an orifice remote therefrom, which consists in establishing a gravity flow from the container to the oriiice and delivering molten giass to the orice faster than it can traverse the same; maintaining the glass at the orice under the expelling force of a substantial and constant head of glass, accumulating a predetermined portion of the excess glass delivered to the orice in a segregation chamber in communication with the orifice, periodically applying an expelling force to the glass in such chamber to accelerate the flow through the orice and closing communication between the container and the orice during the period of accelerated flow to prevent the displacement of the head of glass.

17. A method of feeding molten glass vfrom a traverse the same. maintaining the glass at the orifice under the expelling force of a substantial and constant head of glass, accumulating the excess glass delivered to the orifice in a segregation chamber in communication with the olce and located entirely below theilevel of glass in said container, trapping a `quantity of elastic uid within said-chamber in response to the glass level therein to shut ofi the flow of glass into said chamber and periodically connecting the chamber to a source of fluid pressure to accelerate the glass ow through the oriilce while preventing the displacement of the head of glass.

18. A glass feeder comprising a container for molten glass having an orice in the bottom thereof, a sleeve positioned in said container surrounding said oriilce and communicating with said container, a plunger movable in said sleeve. means for reciprocatingl said plunger, means associated with said plunger for compressing the air within said sleeve on the downward movement thereof, and means for automatically connecting the interior of said sleeve to atmosphere to prevent rarefaction o1' the air in said sleeve on 

